Conventionally, the lubricating device of the automatic transmission in which a lubricating oil is supplied from an oil pump through an oil path in the interior of an input shaft, and such lubricating oil is fed to a lubricating target through an oil path and an oil chamber of each member by a centrifugal force is known. For example, the lubricating device disclosed in Patent Literature 1 includes an oil path and an oil chamber for supplying the lubricating oil to respective engagement unit of a forward clutch, a pinion gear of a planetary gear device for rotating one engagement unit of the forward clutch and one engagement unit of a reverse brake with the input shaft as a center. A partitioning member for allocating the supplied lubricating oil to the respective engagement unit side of the forward clutch and the pinion gear side of the planetary gear device is arranged in the oil chamber. That is, the oil chamber is partitioned by the partitioning member to a space on the pinion gear side and a space on the forward clutch side. In the lubricating device, an oil path for introducing the lubricating oil to the space on the pinion gear side is formed in a member on a radially inner side of the partitioning member. Therefore, the lubricating oil introduced from the oil path to the oil chamber is first fed to the pinion gear side, and the excess is further moved toward the radially outer side. The excess lubricating oil is discharged to the space on the forward clutch side through a through-hole formed in the partitioning member, and then fed to the engagement unit.